Resistive transition and Jc(B) curves in plasma sprayed coatings of YBaCuO superconducting material

Abstract

The critical current densities J c of YBaCuO coatings of the order of 100 μm thick, sprayed using an 80 kW plasma spray system, were found to be in the range 100–200 A cm −2. Resistive transition and J c( B) curves were obtained for low magnetic fields ranging from 0 to 77 Oe at 77 K and 60 K. It was observed that the J c increased by a factor of 4–6 at 60 K. It was also observed that up to 8 Oe, the resistive transitions of the samples were identical, indicating complete shielding against field penetration. At 88 Oe the J c dropped to very low values. The observed trend in resistive transition and J c( B) curves indicates that plasma spray coatings in the thickness range 100–150 μm can effectively be used for shielding applications in low magnetic fields.